A/C clutch not engaging

I could be wrong if the high pressures switch and low pressure switch are analog inputs.

I bought a scanner. There wasn't any faults. A/C system passed. The low and high pressure switches passed. I even unplugged them to see if they would fail, and they did. I was able to force the compressor clutch on with the scanner, that also worked. How can I test the Computer Climate Control(HVAC control Module)? Please show me a Pin out for the Computer Climate Control. What else could hold out the A/C? Is there any inputs to the Computer Climate Control? Please provide diagram. Is there a wire connections, other than ones on the back of the PCM and the Computer Climate Control module that I could un plug and test from? The last picture shows the A/C Relay forced on.

We haven't ruled out everything that could be causing the problem. For instance if the outside ambient temperature is too low something doesn’t all the AC clutch to be activated. The scan tool didn't find anything wrong with the PCM, BUT it did indicate there wasn’t an AC request. I’m not going to replace the PCM before confirming everything else is operating correctly. Isn’t there a temperature sensor on the evaporator?
I didn’t ask you what Pin ID on the back of the PCM. I want a schematic of the computer climate control (it is the HVAC control interface in the dash) so I can see all connected equipment. While we are at it, I want a list of all the Pin IDs on that terminate at the PCM. Both connectors.

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I didn’t ask you what Pin ID on the back of the PCM. I want a schematic of the computer climate control (it is the HVAC control interface in the dash). I want to be able to see all connected equipment. While we are at it, I want a list of all the Pin IDs that terminate at the PCM. Both connectors. Red and blue.

I have attached 2 images of examples of the schematic I'm looking for. Together they show the computer climate control and connected devices. Unfortunately these are not for my vehicle.

I'm not 109% sure but I think so. Here is a picture. There is a small vent in the head liner that I think is for sampling air temperature. I can give the last 8 digits of the VIN if that would help.

Those 2 diagrams are mismatched or there is one in the middle that is missing.

It doesn't look like that diagram is for the computer climate control I have. Mine has 2 Auto settings, 14 position fan speed control.

I also have another temperature sensor in my headliner. The plastic escutcheon grill, which is round and about the size of a half dollar and located just above the driver to the left, is the interior ambient temperature sensor. The sensor is used in conjunction with the automatic HVAC (C68).

What is this sensor clipped onto the AC line downstream of the orifice? It is circled in red in both attached images. You can see the Low Pressure Switch to the right which is unplugged.

Brown and black.

I don't think that diagram is the correct one for my vehicle. That at HVAC control module isn't the same as mine. The AC System makes up just on part of the HVAC system. It works together. Do you have access to provide proper diagrams? This latest diagram doesn't show the temperature that's in my headliner and the HVAC Control Module is different that mine.

According to all the diagrams you have provided the A/C request comes from the HVAC control module, Through the A/C High Pressure Cut Out switch, to the PCM Pin 17. My scanner didn't find any trouble code. The scanner was able to toggle the AC relay proving that portion worked. The scanner reported a fault for the pressure switches when they were disconnected; it even said which switch was disconnected. The scanner also reported a low pressure fault code to the high pressure switch when I forced on the AC relay for too long during cold weather. The scanner indicates it's not getting the AC request. This makes me think it's not the PCM. I don't see anything in any of the info that indicates a faulty PCM. What is the reason you are saying it is the PCM? My thinking is the computer control module isn't putting out an ac request.

What I need to know is how the computer climate control module works, and connected devices effect it's function and the devices are connected to the computer climate control module. There could be a HVAC input device causing the module not to put the ac request or maybe the computer climate control module is faulty or maybe it is the PCM, but until I know for sure before I replace something or get a PCM programed by the dealer.